Voltage-controlled oscillators (VCOs) are electronic circuits that provide an output signal that has a frequency that is controlled, at least in part, by a voltage of an input signal. In practice, a VCO typically includes non-ideal components and the behavior of the VCO may be non-ideal.
A VCO can include an inductor and a switched capacitor bank. Current can flow through the inductor to and/or from the switched capacitor circuit. Current flow through the inductor can impact performance of the VCO.
VCOs can have an output frequency that is controlled in steps. A switched capacitor bank can include capacitors that are selectively switched in and switched out with the inductor to control frequency steps. It can be difficult to control the output frequency as the number of steps increases while maintaining relatively good phase noise performance.